package hadoop;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;

import java.io.IOException;

public class Wordcount {
    public static void main(String[] args) throws IOException, ClassNotFoundException, InterruptedException {
        // 1、获取配置信息以及封装任务
        Configuration configuration = new Configuration();
        Job job = Job.getInstance(configuration);
        // 2、设置 jar 加载路径
        job.setJarByClass(Wordcount.class);
        // 3、设置 map 和 reduce 类
        job.setMapperClass(WordcountMapper.class);
        job.setReducerClass(WordcountReducer.class);

        // 4、设置 map 输出
        job.setMapOutputKeyClass(Text.class);
        job.setMapOutputValueClass(IntWritable.class);
        // 5、设置最终输出 kv 类型
        job.setOutputKeyClass(Text.class);
        job.setOutputKeyClass(IntWritable.class);
        // 6、设置输入和输出路径
        FileInputFormat.setInputPaths(job, new Path(args[0]));
        FileOutputFormat.setOutputPath(job, new Path(args[1]));
        // 7、提交
        boolean result = job.waitForCompletion(true);
        System.exit(result ? 0 : 1);
    }
}
